1) yes
2) not really, but if you don't dial the '1' you will hear a warning about possible LD charges any time you place a long distance call.
3) irrelevant. The tiny amount of data included in all plans is there to cover tiny amounts of data leakage on smartphones. It doesn't apply to landline phones.
4) probably, but I'd recommend testing it with a couple of short calls the first month, rather than potentially running up a huge bill. Koodo doesn't guarantee that third party calling services will work.